Solution to browser back button click event handling

By | December 10, 2013

In Javascript, onbeforeunload event is fired when the page is about to unload and there can be multiple reasons for this unload. For instance, back or forward or refresh button is clicked or a link on the page is clicked etc.Normally, onbeforeunload event is used in order to handle browser back button functionality as follows:

    <body onbeforeunload=”HandleBackFunctionality()”>
    function HandleBackFunctionality()
    {
           if(window.event) //Internet Explorer
           {
                     alert(“Browser back button is clicked on Internet Explorer…”);
           }
          else //Other browsers e.g. Chrome
           {
                     alert(“Browser back button is clicked on other browser…”);
            }
     }

But there is a problem that identical event occurs once a user clicks on refresh button of a browser. So, to grasp whether or not refresh button or back button is clicked, we will use the subsequent code.

          if(window.event.clientX < 40 && window.event.clientY < 0)
          {
                   alert(“Browser back button is clicked…”);
          }
          else
          {
                   alert(“Browser refresh button is clicked…”);
          }

Above code snippet works well in browsers aside from FireFox, In case of FireFox, we need to apply the following check.

         if(event.currentTarget.performance.navigation.type == 1)
         {
                   alert(“Browser refresh button is clicked…”);
         }
         if(event.currentTarget.performance.navigation.type == 2)
        {
                  alert(“Browser back button is clicked…”);
        }

So, consolidated code snippet will look as:

            function HandleBackFunctionality()
           {
                   if(window.event)
                   {
                          if(window.event.clientX < 40 && window.event.clientY < 0)
                          {
                                     alert(“Browser back button is clicked…”);
                          }
                         else
                         {
                                     alert(“Browser refresh button is clicked…”);
                          }
                   }
                  else
                  {
                           if(event.currentTarget.performance.navigation.type == 1)
                           {
                                    alert(“Browser refresh button is clicked…”);
                           }
                           if(event.currentTarget.performance.navigation.type == 2)
                           {
                                     alert(“Browser back button is clicked…”);
                            }
                   }
          }

Above code snippet is beneficial in many scenarios however there are some issues with it. For instance, navigation can be done using keyboard keys and refresh can also be done using F5 or CTRL+R which can not be handled using above code.

In order to handle back button functionality, we need to come up with a solution that requires server-side effort together with client side Javascript code.
So, what’s the concept is…?
We will store the current page URL in session variable (say CurrentPageURL) on a page. When moved to another page, we will get that variable value and store in a second session variable (say PreviousPageURL) and update CurrentPageURL session variable with new page URL. ASP.NET straightforward code implementation is as follows:

         //ASP.NET/C# code
        if (Session["CurrentPageURL"] != null)
        {
                    Session["PreviousPageURL"] = Session["CurrentPageURL"];
        }
        Session["CurrentPageURL"] = Request.Url;

On client side, when onbeforeunload event is fired, we will verify that whether or not Javascript document.referrer value is same as that of the session variable? If the value is same, means back button is clicked, so will act accordingly.

           function HandleBackFunctionality()
          {
                      var previousPageURL = “<%= Session["PreviousPageURL"] %>”;
                       if (document.referrer == previousPageURL)
                       {
                                  alert(“Its a back button click…”);
                                  //Specific code here…
                        }
           }

This solution works well regardless of the browser type and simple to implement. Server-side implementation in other languages is also straightforward. Please feel free to comment and suggest a better idea (if any).


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  • http://www.blogger.com/profile/07213216056147724931 azhar baig

    Excellent solution find you.
    Thanks for posting Web Application Development services

  • Shubhra Jain

    Nice solution to a very common problem

  • Thirumala Reddy

    I am copy past the your code i got this exception “event is not defined ”
    In this line “event.currentTarget.performance.navigation.type”.
    i am using only html and java script

    • http://www.webdevelopmenthelp.net/ WebdevTutorial

      Reddy,
      Can u please tell your browser and it’s version? I tried IE and Chrome and it’s working fine.